Viscous cosmologies with variable {lambda} in higher derivative gravity

Journal Article · Sat Dec 15 04:00:00 EST 2007 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.76.123505· OSTI ID:21024013

Debnath, P S; Paul, B C; Beesham, A ^[1]

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1. Physics Department, P. O. North Bengal University, Siliguri, Dist.: Darjeeling, PIN: 734 430 (India)

We obtain cosmological solutions in higher derivative theories of gravity in the presence of an imperfect fluid and a time varying cosmological parameter ({lambda}). We explore both power-law and exponential expansion of the universe considering an imperfect fluid described by the Eckart, truncated, and full causal theories proposed by Israel and Stewart. We discuss the physical and geometrical features of the models in the presence of a known time varying {lambda}. The interesting feature of the models is that they admit accelerating universes in some specific cases. The evolution of the temperature of the universe in the framework of the full causal theory is also determined.

• OSTI ID: 21024013
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 12 Vol. 76; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CAUSALITY
COSMOLOGY
GRAVITATION
MATHEMATICAL SOLUTIONS
UNIVERSE
VISCOSITY